Expectation variables

Dear dynare team, if I have a expression like this,
20190819
Then how to write in dynare model block, thanks a lot.

My best,
ZL, Jiang

My take on this is that you should use your model to derive an expression for the conditional expectation term in terms of observable and input it.

Either you manually introduce auxiliary variables (see e.g. Expected value of a power) or you use Dynare’s EXPECTATION()() operator (see the manual).